Over winter break I started on a project I’ve been wanting to do for a long time. A coffee cup stirling engine, made from scratch based on plans from Jan Ridders.
It “almost works”. The bearings seem to be too big, and the shaft has a lot of slop. I had machined the shaft to the side I thought the bearings were going to be (3mm), but they are larger! I need to remake that part and see if it works.
Some work in progress shots. Power piston (graphite), cylinder (brass), crank shaft (steel), flywheel (alum), stand (alum in brass).
Several tries to get these right:
Flycutting stuff and testing the displacer fit in the groove.
I’m working on a V-Frame 36′er unicycle, called the “Corbin V-36“.
It’s partially an experiment to see how light I can make it, yet still be strong and not flex.
I did a 3d model in Sketchup, and printed it full size. I then machined a jig to hold things in place. Here’s a video explaining the jig:
And some pictures. The jig setup for my my main seat post tube:
Experimenting with bending:
I’m using cro-moly tubing, 1/2″ OD by .049 wall thickness. It is too small of tubing, and the frame flexes when going up hills. I’m going to use 7/8″ tubing next, and try to re-enforce this frame.
Working the corners in my jig:
Jig and frame almost setup to weld the front post tube:
Clamped together, and brazing started:
Popped out of the jig and a test fit:
Setting up the main seat post:
After it was brazed on:
Horizontal support, bent to match the tire diameter, brazed on, and a test handlebar tossed on:
The frame flexes *a lot* going uphill. I have to use larger tubing for the seat post to fix that. I brazed on some lower supports to try to prevent flex, but it didn’t help much. I’m going to braze on another tube really close to my seat post to try to get this frame to work. Then, if it does, I’ll make another one with thicker tubing.
Due to heat distortion, I had to ream out both tube holes to get the stuff to go into them.
…well, problems come in pairs. I changed my front brake pads about about 8600 miles; they wore away quickly! I didn’t change the rear, as they weren’t as bad as the front. I checked the new front ones at 15,000 miles and they are doing great. I had looked at the rear but only on one side and without taking the wheel off. They looked okay, so I wasn’t going to do them yet. However, the rear brakes started making a horrible noise last Friday.
So today I decided to take the brakes apart and drop in the new pads I already had on hand. It turned out to be an all day adventure. The left pads were worn, and it was time to replace them, but they weren’t totally shot. The right rear wasn’t in such good shape. Of the two pads, the left pad wore twice as fast, and was starting to etch into the disc! Doh! It wasn’t that bad, and I’m not going to replace the disc, but I had some trouble with installing the new pads. First of all, the pistons on the calipers were not wanting to go back in. I had to force them in with a pretty large C-clamp, and even then it was a lot of effort to get them in. Then I encountered the “problem”.
I have the rear disc brake conversion kit from CIP1. It is this one. It turns out one of the bolts that moves in and out to let the brake adjust was seized. So instead of moving as the pads wore, it just stayed put, and caused one side of the pad to wear twice as fast as the other! Worse, it was impossible to get off. I tried lots of things, including heating it with the torch, but it wasn’t budging. I put a bolt in and tried to get it to move…but that was a bad idea as the bolt snapped right off! That made things worse. I took the piece off the car and worked it in my vice and finally got it out.
In the picture below, the bottom right hole is where it was stuck; I managed to get it out by working it in a vice for a while.
The stuck piece freed:
Apparently some water got in the hole and let things rust up nice and bad. The sucky part is that I broke the bolt off in the piece:
..and easy outs (bolt extractors) *never* work for me. So, I of course broke one off in it.
I wasn’t sure what to do. I could order a new caliper (i.e.: this one). for $120 plus shipping, and wait a week to get it…but I don’t want to do that as it means week of not driving and I also have a car show to go to next Saturday! Instead, I decided to machine my own piece. So, after some time on the lathe and mill I had a replacement.
In the picture below, the top is the broken piece, the middle is the good piece+bolt, and the bottom is what I made. After the picture was taken, I quenched it in oil to harden it (note to self: don’t do it in a plastic container).
The finished piece is on the right, and the material I used is the big lump of steel.
My short test drive seems to let the brakes work! Cool…it only took all day (~10am to 8pm). And I missed hanging out with my friend Nathan for his birthday! Doh…
I’m doing a series of videos on how I made my second Roue Cyr (Cyr Wheel — aka: Simple Wheel).
Here’s the last in the series…which is skinning.
Updated notes: Use pipe clamps to secure the air attachment on! Heat it in the oven for ~3 minutes. Spray water on it from a bottle if it has trouble going over. If this method doesn’t work, the alternative is to skin the wheel while it is hot bath water, and then let it dry out for a few days before assembling.
I wanted a new pull-up bar for my house. The old one looked tacky…but how can anything be tacky around your own house if you put it there? Here’s some shapes cut out of metal:
Pieces setup for welding:
Ugly pullup bar removed:
Hanging on the wheel (as seen through the eyes of a lyra. And in this picture you can see how the top right of the lyra wasn’t quite as circular as I wanted…)
I needed somewhere better t hang my cube when I wasn’t using it. So, I made a cube hanger!
I used the plasma cutter to cut some pieces of 3/16′ish steel plate (from the scrap yard):
Cut out:
I TIG welded on some 1.5″ pipe at a 45 angle:
Cleaned it up, and powder coated it flat black:
Bolted it to my beam (it is super strong!):
And hang the cube! It is a little close to the wall, but out of the way. It is kind of fun to sit in it, so I’ll probably whip up another one more in the center of the room to hang for parties and stuff.
I got a new tool a few weeks ago. A plasma cutter!
After doing some research, I went with a Thermal Dynamics Cutmaster 52. It is awesome!
I also had to get a new air compressor to keep up with it. I went with a Husky one from Home Depot; it has a three year warranty, whereas most other ones of the same size have a 1 year warranty. Plus, there were lots of good reviews on HomeDepot.com.
The fan in the window is used to exhaust fumes from welding and other things:
Nuts, bolts and Bengal cat:
JET drill press:
Metal stock:
MATCO welder (I bought it used) and oxy-acetylne setup behind it to the left:
Grizzly G0555 wood bandsaw. Works well for the small shop, although a few times I have wanted a wider throat.
Grizzly 8″ jointer; I bought a good large jointer, but I have only used it a few times so far:
The dust collection system lives behind the garage in a little shed I built just for it. Here is a post when I setup dust collection in the shop. The buttons on the wall turn it on and off:
1990 Enco Milling machine. Awesome! I bought it used, but it has been working great since I did some tune ups on the belt.
Milling tooling and accessories:
Powder coating oven given to me by Eric (thanks!). On top of it is my powder coating supplies. The 50 amp outlet for it on it is also used to charge my car. To the top right of it in the gray box is an American Rotary phase converter than generates 3 phase for the mill.
Southbend lathe from the 1950′s
Misc storage and stuff:
The latest addition; Grizzly 36″ slip roll:
Router table to the right of the table saw. Underneath is a jig saw and router:
Grizzly horizontal metal bandsaw with swivel head. One of the most used tools for metalworking, and definitely a must have for doing any kind of metal work. The swivel head is also GREAT.
Grizzly G0444 contractor table saw. A little underpowered, and eventually I will get a full size cabinet saw with a riving knife (for extra safety):
Overall, I have bought a lot of Grizzly tools. They are fairly priced, and I find the quality to be quite good for shop use. I have had no real problems with the Grizzly tools. They are definitely better than the Enco brand tools (although, the mill I have is of decent quality), and light years ahead of Harbor Freight tools (which I won’t buy, unless it is for a one time project).
Tuner’s Cube. I made it for my dad for Christmas 2010. Aaron helped me over Thanksgiving break to figure out the details and did some machining on it too. It started out as a ~3.5″x3.5″ solid square piece of aluminum.
We made a jig to hold it so it could be removed and place back in again at the same position but on a different edge.
The rotary table on the mill was used to turn it out:
Second half of the jig — this was Aaron’s idea, and it worked great. Just use a piece of mild steel with a hold cut into it and clamp it down on top.
